Android: We often set alarms and reminders for ourselves based on the time of day, but what if you want to remind yourself of something based on where you are? GeoNote does just that, letting you set GPS-based notifications on your smartphone.

In this age of email, I often forget to check my snail mail, which doesn't make my mailman very happy once the mailbox starts overflowing. I'd like to remind myself to check my mail as I come home, but setting a timed alarm isn't exactly ideal for reminding myself to check the mail on my way home. GeoNote gets around this problem by letting you send yourself location-based notifications with your smartphone. Just set up a new note, attach it to a location (by address or by GPS auto-location), and set the notification you want to send. You can have it send you the notification when you enter or exit a certain radius of the location, too, making the notifications much more reliable.

GeoNote is a free download for Android devices running 2.1 and up. There's also a $1.99 ad-free version.